Swivel base construction



March 14, 1933. w. A. RANKI'N 1,901,120

SWIVEL BASE CONSTRUCTION I Filed Dec. 18, 1951 2 sneetsheen 1 March 14, 1933. w` A RANKIN 1,901,120

' SWIVEL BASE COSTRUCTION Filed Dec. 18, 1931 2 Sheets-Shea?l 2 Patented Mar. 14, 1933 UNITED STATESV PATENT ortica WILLIAM A; RANKIN, OF ROCK ISLAND, ILLINOIS, ASSIG'NOR TO BIRTMN ELECTRIC (COMPANY, OF GHICAGO,ILLINOIS, A CORPORATION 'OF ILLINOIS .SWIVEL BASE CONSTRUCTION' Appneation inea December is, 193i. seriai No. 581,970. y

This invention relates to improvements in swivel base construction. For the purpose of illustrating one use of my invention, I have shown the same incorporated in a swivel vise or a vise with a swivel base. vIt is to be understood, however, that the invention is not limited to use with vises, but may be employed in connection with other machines, devices, and the like. i p

I'Ieretofore, vises of the character referred to have lacked rigidity and firmness between the base `and the body when clamped in position. This has been due to the ordinary twopoint support (not considering the pivot) which permitted a certain amount of rocking of the body. One of the-features of my invention is the provision of a construction furnishing a three-point support, thus making the body firm, steady and rigid on the base `in any of its clamped positions. Y y

A vise of the characterreferred to is provided with a base member and a body member pivotally mounted on the base, ordinarily by a screw or bolt in the center.v A clamping screw is arranged at one side. In the older Y constructions, when the clamping screw is screwed in against the base, the body rocks slightly on the pivot screw as a fulcrum and makes contact with the base at a point diametrically opposite the clamping screw. There is thus a two-point contact or support (disregarding the pivot screw), namely, at the clamping screw and a point diametrically opposite. This two-pointsupport permits a slight rocking of the body on the base.

In the practice of my invention, I eliminate this two-point support and provide a threepoint support instead. In one embodiment of the invention I accomplish this by recessing the body through an arc of about 100 opposite the clamping screw, so that when the clamping screw is turned in against the base, the body will rock slightly and make contact with the base at two points instead of one, these two points being separated about 100 and each being about 130o from the clamping screw. There will thus be a three-point support between the body and base giving a very firm, steady and rigid mounting in any position of the body.

In another embodiment of the invention,

I provide three bolts between the body and the base spaced substantially 120o apart about the pivot point. The base and body are Figure 1 is a view inside elevation; Fig.r

2 is a view taken as indicated by the line 2 of Fig. 1; Fig. 3 is a fragmentary view of the body and base inrear elevation; Fig. 4

is a .view taken as indicated by the line 4 of Fig. Fig. 5 .is a view taken as indicated by the line 5 of Fig. l Fig. 6 is a view similar to Fig. 2 of a modiied form showing a seotion taken as indicated by the line 6 6l of Fig. 8; Fig. 7 isa view of the body looking upwardly; F ig.4 8 is a view of the base looking downwardly and Fig. 9 is a view showing a modifiedform of adjusting bolt.

As shown in the drawings, the vise includes' a .circular base' member 10 provided with the usual perforated ears 10a permitting it to be fastened to any suitable support 11, as by the lag screws 12.

The top of the base 10 maybe provided with notches orserrations 10b `to assist in holdingthe clamping screw in its desired location. o Numeral 13 indicates a circular body member pivotally mounted onthe base 10 bythe usual screw 14.` yNumeral 15 indicates the usual separating lbushing member on v the screw 14 to prevent the body 13 frombeing too closely drawn against the baselO when the screw is tightened. In other words, there must be a slight play between the members 13 and 10 to permit rotation 4of the vise on the base when the clamping screw is loose.'`

The body member 13 supports the body inthe ac proper 16 of the vise and 17 'indicates the usual movable j aw of the vise. j

At one side of the swivel screw 14 the body member 13is provided with the clamping or retaining screw 18 adapted to be screwed down against the base 10 to hold or support f the vise in its clamped position. The lower end 18a of the screw 18 is adapted to engage in the serrations 10b.

The particular' feature of my invention is the recessing ofthe underside of a portion of the periphery of the body member 13 opf posite the clamping screw 18. Y Such recessing is clearly shown in Fi gs.,3 and 4, as indicated by 19. yThis recess extends through substan- VVtially 100o and terminates in shoulders 19,

19-. vWhen the clamping screw 18 is screwed in againstthe base 10, the body 13 rocks slightlyY on its pivotal mounting to cause the shoulders 19, 19a to be brought into contact with the base. This will give three supporting points or retaining elements spaced about the airis of the pivot, said three points being the, vertically adjustable clamping Y screw 18 and the other two, the shoulders I shall now describe the form of invention embodied in the construction shown in Figs. 6, and 8. Asfhere shown, the bodyV body 113. There is also provided a third adjustable retaining, clamping or supporting bolt 122% the head 121a of which also lies in the slot 120. The nut'123a on` this bolt is provided with a pin 123.b to permit ready .L adjustment of the same.

In the operation of the structure as shown in Figs. 6, 7 and 8, when the bolt 1221'is tightened, the body 113 rocks slightly on its pivotal mounting to cause the bolts 122 to I tighten up. The three bolts are spaced substantially 120". apart and, consequently, Vthis will give three supporting points spaced about the axis of the pivot, said three points being the three bolts.

In Fig. 9.. I have shown another form of clamping screw that could be used instead of the clamping screw 18 of Fig. 2. As shown in- Fig. 9 the clamping screw is indicated by 218 and insteadrof being threaded in the body member 213,l theV same goes through a plain hole. The member 213 is provided with a recess 213:* accommodating the nut 230. When the screw 218 is turned down, the nut 230is held against rotation bythe walls ofthe recess 213av and this causes upward pressure against thel member 213. It is understood, of course, that the lower end of the screw 218, as indicated by 21821, en-V elty'inherent in my invention as broadly as permissible, in view ofthe prior art.

l/Vhat I regard as new, and desire to secure by Letters Patent, is:

1. Swivel base construction, including; a`

base member; a body member pivotally mounted on the base member; and a clamping screw carried by one of said members, said member having a portion of its periphery recessed opposite said clamping screw whereby tightening ofthe clamping screw willv cause engagement between said members at twoV points opposite said clamping screw.

2. Swivel base construction, including; a base member; a body member pivotally mounted on the'base member; and a clampjing screw carried by the body member, said body member 'having a portion of its periphery recessed opposite said clamping screw, whereby tightening ofthe clamping screw will cause contact of the body member with the base member at two points opposite said clamping screw. i

. 3. Swivel base construction, including; a base member; a body member pivotally mounted on the base member and spaced therefrom around the pivotal mounting, said spacing imposing a limited zone of reaction; and three clamping bolts carried by one of said members and engaging the other, said bolts being spaced about the axis of the pivot and vfrom and about said zone of reaction to the clamping stress, and one of the same being` adjustable. l i

4.y Swivel base construction, including; a base member; a body member rotatably mounted on the base member; and means for anchoring the body member against rotation, f

said means imposing astress in one direction at one point, and a stress in the opposite di. rection at three separate points surrounding said rst point.

In witness whereof, I have hereunto set my hand this 11th day of December, 1931.

WILLIAM A. RANKIN. 

